From the Guidelines
Seroquel (quetiapine) is an effective atypical antipsychotic medication for treating schizophrenia, bipolar disorder, and major depressive disorder, with a recommended dosage ranging from 25mg to 800mg daily, depending on the condition and individual patient factors 1.
Key Considerations
- The medication is available in immediate-release and extended-release formulations, with common side effects including sedation, dizziness, dry mouth, weight gain, and metabolic changes 1.
- Regular monitoring of weight, blood sugar, lipids, and other metabolic parameters is necessary during treatment 1.
- Patients should not stop taking Seroquel abruptly, as this can cause withdrawal symptoms, and the medication should only be used under medical supervision 1.
Dosage and Administration
- For schizophrenia, doses usually range from 300-800mg daily, while bipolar disorder may require 400-800mg daily 1.
- When used for depression or insomnia (off-label), lower doses of 25-200mg are common 1.
Mechanism of Action
- Seroquel works by blocking multiple neurotransmitter receptors, particularly dopamine and serotonin receptors, which helps regulate brain chemistry associated with psychotic symptoms, mood stabilization, and sleep regulation 1.
Special Considerations
- The medication should be used with caution in older patients and those with hepatic impairment, and the dose should be reduced accordingly 1.
- Seroquel may cause orthostatic hypotension, dizziness, and sedation, and patients should be monitored for these side effects 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Overview of Seroquel (Quetiapine)
- Seroquel, also known as quetiapine, is an atypical antipsychotic medication used to treat schizophrenia and bipolar disorder.
- Studies have compared the effectiveness of quetiapine with other atypical antipsychotics, including olanzapine, risperidone, and ziprasidone.
Efficacy of Quetiapine Compared to Other Atypical Antipsychotics
- A study published in 2010 found that olanzapine and risperidone were more effective than quetiapine in treating schizophrenia, as measured by the Positive and Negative Syndrome Scale (PANSS) total score 2.
- A 2013 study found that quetiapine was less effective than olanzapine and risperidone in treating schizophrenia, but the clinical meaning of these findings is unclear 3.
- Another study published in 2006 found that risperidone and olanzapine were more effective than quetiapine in treating patients with chronic schizophrenia who had discontinued a previous atypical antipsychotic 4.
Side Effects and Tolerability of Quetiapine
- Quetiapine has been found to produce fewer movement disorders and less weight gain than olanzapine, but more QTc prolongation 2, 3.
- Quetiapine has also been found to induce fewer extrapyramidal adverse effects and less prolactin increase than risperidone, but more cholesterol increase 2, 3.
- A study published in 2007 found that quetiapine may be inferior to olanzapine and risperidone in symptomatic patients with schizophrenia, with a lower response rate and more treatment failures 5.
Mental Health Resource Use and Costs
- A study published in 2005 found that there were no significant differences in mental health resource use among patients treated with quetiapine, risperidone, or olanzapine for bipolar disorder 6.
- However, the study found that olanzapine was more costly than quetiapine and risperidone at an equivalent daily dose.